Sliding door latch



v. s. MILBURN 2,540,686

SLIDING DOOR LATCH Feb. 6, 1951 Filed June 4, 1946 d INVEN OR AQ A11 QNEYS Patenied Feb. 6, 1951 sumNG Dooa LATCH vernos s. Milburn, Pittsburgh, n., mi or u McKinney Manufacturing Company, lPittsburgh, Pa., a corporation o! Pennsylvanls Application June 4, 1948, Serial No. 674,2 i4

l Claim. (Cl. 292-124) This invention relates to locks or latches, and

'more particularly to those particularly suited for use with sliding doors.

It is among the objects of this invention to provide a sliding door latch which can be locked by a key from one side and by a self-contained locking member from the other side, which will permit the door to be closed even though the latch is locked, which is of simple and inexpensive construction, which can hold a sliding door either open or closed, and which is sturdy and dependable in operation.

In accordance with this invention a bolt projects irom one side of a case in which the inner end of the bolt is pivotally mounted. The bolt normally is held in operative or latching position in any suitable manner, such as by a spring. Inside the case there is manually operable means by which the bolt can be swung from latching to inoperative position by turning a handle or knob outside the case. In order to be able to lockthe manually operable means from in front oi the case, key operated means are provided in the case. These means may include a locking member and a key actuated member for moving it into engagement with the bolt-actuating means so that the latter cannot move. Also mounted in the case is a manually operable member which prolects therefrom for locking the bolt-actuating means from in back of the case. This member preferably is in the form of a bar slidably mounted in the case and shaped to obstruct movement oi' the bolt-swinging means when the bar is slid in a certain direction. This locks the bolt-swinging means independently of the other locking member. No key is required for moving the bar. By using a pair of bolts projecting from opposite sides of the case, this latch can be used for locking a sliding door either in open or in closed position or, if the latch is mounted on a separating strip, it can lock two sliding doors that are slid toward the strip from opposite directions.

The preferred embodiment of the invention is illustrated .in the accompanying drawings in which Fig. l is an isometric view of my latch; Fig. 2 is a front view of the latch with the cover removed; and Fig. 3 is a vertical section taken on the line III-IH of Fig. 2, but with the cover in place.

Referring to the drawings. a case is formed from a metal sheet which has its edges turned st right angles to form side walls l and its ends bent to form upper and lower end walls 2 provided with vertical projections I. A flat cover plate I is connec ed to the front of these Droiections by any suitable means, such as by screws I. Near the boti om of the case the opposite side walls are cut away to form openings 'i through which a pair o1' bolts l extend. The inner ends of these bolts are reduced in thickness and over lap each other, their overlapping portions being provided with aligned openings through which extends a pivot pin 8 rigidly mounted in the back wall of the case and projecting into an opening in the cover plate. The outer ends of the bolts. whict are provided with .upwardly projecting hooks, therefore can be swung up and down on the Divot pin. Normally the bolts are held in their upper horizontal position by vertical coil sprin gs I0 compressed between them and the lower ws il of the case.

Either one of mese bolts can be swung down against the resistance of the underlying spring lil by means of ai x actuating member or depresser i2 that has munded lower corners engaging the tops of the bolts. This depresser is rigidly mounted on a cylindrical member il rotatably mounted in the rear wall of the case provided with a square axial passage I4 for reception of a square shaft Iii carrying knobs or handles l1 so that the depre sser can be turned from either the front or the back of the case. When the depresser is tun led, one lowerl corner or the other presses down on the underlying bolt. depending on whiel` way the depresser is turned.

Provision is m1 de for locking this latch from in front of the case, i. e. outside the door, by means o! a key For this purpose a locking plate 2|, disposed in the upper part oi' the case.' is slidable vertice' `ly therein and is provided with rearwardly projecting side flanges 22 which engage the cover an :l thereby hold the slide against the back of the nase. The central part of the plate is provided with a generally rectangular opening Il in wh; ch a circular cam 24 is rotatably mounted. Tllis cam is rigidly mounted eccentrically on a small cylindrical member 2l which in turn is rotatably mounted in the rear wall of the case. Member Il is provided with a square axial passage Il that receives the square shaft 2l of a key )perated lock' (not shown) that may be mounted in front of the case in the usual way.

When a key is turned in the lock. it turns shaft 2B and thereby rc tates the cam 180 to move the slide downwardly toward depresser i2. The adjacent portions ci the slide and depresser are provided with inta rengaging detents s o that when the slide is moved down it will engage the dspresser and prevent it from being rotated. Pre-i'- erably, the top oi the depresser is provided with a lug Il that proiects forward, while the lower edge oi' the slide is provided with a vertical notch Il adapted to nt down snugly over the lug to hold the depresser against rotation. However, it will be seen that even when the depresser is held stationary by the slide, the door to which this latch may be attached can be closed because the pressure oi' the outer end o! one of the bolts against the keeper on the door frame can swing that bolt downwardly away from the depresser and allow the bolt to snap into engagement with the keeper, where it will remain until the slide is raised away from lug il by means oi the key-operated cam 24.

Another feature of this invention is that the latch can be locked, from in back of the case. i. e. inside the door, without the use of a key. Accordingly. a vertical locking bar 85 is slidably mounted in the case between ric-presser I2 and cover plate 4. The upper end of the bar is pro vided with a tongue I6 that extends up through a notch in. the front edge ci the upper wall oi' the case and then rearwardly. The lower end oi the bar is pressed against the cover by a leaf spring 31 attached to the lower end oi' the rear Wall of the case, while opposite sides of the upper portion of the bar are cut away to accommodate flanges 22 on slide 2|. The lower portion of the bar is provided with a vertical slot 38 through which pivot pin 9 extends. This pin controls the distance the bar can be moved up and down in the case The central portion oi' the bar is provided with an opening 39 to aceommodate the handle shaift I6, and the upper portion oi' the bar is provided with an opening 4| for key-operated shaft 2B.

Extending downwardly in the bar from upper opening Il is a'recess l2 into which depresser lug )i normally projects. This recess is wide enough to allow the-lug to swing back and forth in the bar when the depresser is turned in either direction by one oi the handles in order to depress one oi the bolts 8. However, at the bottom of recess 42 there is a central vertical slot 43 which receives the lug when the locking bar is lifted by its tongue 35 from the position shown in the drawings. As this slot is substantially no wider than the depresser lng, it prevents the lug from being moved and thereby holds the depresser stationary when slide 2i is in its upper, inoperative position. nr; down on tongue 36, slot il is moved below si.. 4depresser so that the depresser again can are turned in either direction.

The latch disclosed herein is particularly useful for sliding doers on the sides oi trucks where it-ls desirable to be able to lock the doors quickly from the inside without having to bother with keys. with this latch it is only necessary to litt the locking bar tongue with the nnger to lock the latch, or depress the tongue to unlock the latch. Outside of the truck the latch can be locked safely with a key. The latch itself has' only a i'ew parts and can be made inexpensively and assembled quickly, Most of the parts are stamped out, and there is practically nothing to get out oi order. y

According to the provisions of the patent statutes, I have explained the principle and construction oi' my invention and have illustrated and described what I now consider to represent its best embodiment. However. I desire to have it understood that, within the scope o1' the appended claim, the invention may be practiced otherwise than as speciiically illustrated and`described.

I claim:

A sliding door latch comprising a vertical case, a bolt projecting from a side of the case into latching position, means pivotally connecting the inner end of the bolt in the case on a horizontal axis, a manually oscillatable member in the case for swinging the bolt out o1 latching position, said member being provided with a lug portion spaced vertically from and projecting substantially parallel to the axis of that member. and a vertical locking bar slidably mounted in the case beside said member and projecting from the end of the case that is adjacent said lug portion, said bar being provided with a recess normally receiving said lug portion and of suiiicient width to permit the lug to swing sideways so that said oscillatable member can be turned, and said bar also being provided with a slot leading out of said recess toward the axis of said member tor receiving said lug portion and holding it substantially stationary when the bar is slid toward said end of the case into locking position. A

' VERNON S. MILBURN.

REFERENCES CITED The following references are of record in the tile oi this patent:

UNITED STATES PATENTS FOREIGN PATENTS Country Date y Switzerland Jan. 16, A1924 France Aug. 31, 1915 Number Number 

